Development of the Variable Multi-ejector for a Mini-bus PEMFC System

The ejector for the hydrogen recirculation system is necessary to improve the efficiency of the fuel cell mini-bus system. However, conventional ejector does not keep the good performance throughout the wide operating range though the mini-bus system requires the various power form the fuel cell. In this study, the variable multi-ejector acceptable in the whole power range required from the mini-bus is developed. Consequently, the entrainment ratio of the developed ejector is verified by the experiments based on the real operating conditions during the city tour mode.